Author Topic: Modification of the DBS-22 By Kurt Johansson of Sweden  (Read 18070 times)

Offline Elden

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Re: Modification of the DBS-22 By Kurt Johansson of Sweden
« Reply #15 on: November 01, 2017, 05:25:08 am »
   I am working toward posting some more pictures of the modification as I did it as well as comments about it.
Elden

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Re: Modification of the DBS-22 By Kurt Johansson of Sweden
« Reply #16 on: November 01, 2017, 11:56:31 pm »
Part 1   Additional pictures and comments in regard to Curt's  DBS-22 modification

   In response to more than one request for further information about Curt's modification to the DBS-22, I will attempt to show what I have done to mine. I can not guarantee that the position of my pivot (fulcrum) point is exactly located where Curt's is. His jig appears to be just a little different than mine. His pivot (fulcrum) bolt is a little larger and the jig cosmetically is a little different. As I have stated previously, I do not feel that the exact position of the hole is a super critical issue. Following his instructions with his pictures will get you there.

   I do not recommend drilling the through the existing hole in the top plate, rather use it to mark the location on the bottom plate through it, then drill the hole with the top plate out of the way.  Transfer punches work great for marking, but are not an absolute necessity (I did not use one).This is soft material and it would not take much to wallow out the existing hole in the top plate if one was to drill through it.

   The following instructions and pictures were made after my modification was done. Thus, my comments are about what it appears that I did. Curt's words are contained in quotation marks.

   The photography is poor. Most of the pictures are from my ancient flip phone. However, not being for a photo contest, I believe they will work.
______________________________________________


   " First lock the screw at P but not to hard," 
 Trying to match the location shown in his photo the best I could, the pointer was close to 140° on the scale. 
(See 1st picture)  Tighten the locking screw enough to keep the adjustment from sliding but still it allow to pivot on that screw.

   " then remove the fulcrum bolt, "   
(2nd picture)    Measure the diameter of the pivot (fulcrum) bolt after removing it so that you will know what size of hole to drill.

   " next swing the plate counter clockwise te till the position on the picture."   
(3rd picture)
(4th picture)
Note the position of the pointer in relationship to the bottom plate. This helps with the location process.
The 4th picture is much the same as the 3rd but maybe a little less blurred. The 3rd showed the upper part of the plates for added location purposes.

   " After that lock the screw at P fairly hard and drill a new hole trough the bottom plate using the existing hole on the top plate as a starting point. Please note that you have to take in account the underside of the top plate so that you do not interfere with the slides under the top plate."   
 Tighten the locking screw sufficiently to stop the pivoting  action. Again as I stated above, I do NOT recommend using the hole in the top plate as a guide for the drill bit. However, it is your money involved, not mine! Mark the position of the new pivot (fulcrum) hole on the bottom plate through the hole in the upper plate. As Curt stated, make sure the hole (consequently the pivot (fulcrum) bolt) you intend to drill will not interfere  with the slides. Mine did not interfere. I recommend separating the top and bottom plates for drilling. Drill an appropriately sized hole according to the diameter of your pivot (fulcrum) bolt.

   (5th picture)  The underneath side of the bottom plate with new hole and bolt beside it.

   I am reluctant to state dimensions for the location of the hole. I will give what they are close to for mine. Just be aware they are approximate, close figures for my unit. Consider them only as a reference that you are close to the same area. Castings and machinigs can be different.

(6th picture) shows the measuring of what I call from the side.   1.550 inches  (39.37 mm)  to the center of hole from the side

(7th picture shows the measuring of what I call from the end. 1.150 inches   (29.21 mm) to the center of hole from the end

REMEMBER: DO NOT ESTABLISH THE LOCATION OF THE NEW PIVOT (FULCRUM) HOLE  BY THE DIMENSIONS GIVEN IMMEDIATELY ABOVE. INSTEAD USE THE PROCEDURE GIVEN IN THE METHOD GIVEN ABOVE.

   As I have more than 8 pictures, this discussion will be continued in part 2.

« Last Edit: November 02, 2017, 09:20:40 pm by Elden »
Elden

Offline Elden

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Re: Modification of the DBS-22 By Kurt Johansson of Sweden
« Reply #17 on: November 02, 2017, 03:28:16 am »
Part 2   Continuing Additional pictures and comments in regard to Curt's  DBS-22 modification

(1st picture) underside of the bottom plate with the pivot ( fulcrum) bolt installed in the new pivot (fulcrum) hole

(2nd picture) upper side of the top and bottom plate positioned on the slide with pivot (fulcrum) bolt installed in the new pivot (fulcrum) hole

(3rd picture) unit with drill bit holder in position with a spade bit inserted.  Note this was just for the picture. I have not set it up to the grinder yet, so the protrusion may not be correct. The top plate is rotated fully counterclockwise.

(4th picture) Same as the 3rd picture, however, the top plate is rotated fully clockwise.

(5th picture) Same as the 4th picture, but with the drill bit holder flipped 180° to second sharpening position.

   Final thoughts for now: There seems to be a fair range of motion in the angle adjustment. I imagine it is sufficient for most spade bits. It would not be difficult to add more pivot (fulcrum) holes if needed for more exotic angles. I am not sure if I have the other style of bit, but Curt has shown one of those in  his pictures.

   I hope this helps.

« Last Edit: November 02, 2017, 03:36:01 am by Elden »
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Offline tgbto

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Re: Modification of the DBS-22 By Kurt Johansson of Sweden
« Reply #18 on: March 19, 2021, 08:48:56 am »
I know I'm unearthing an old subject, but I have a few Festool brad point bits that have gotten quite dull.

So I think this modification might help a lot, as the Tormek is the only grinder I can use for this. I was wondering what you would suggest as far as the wheel for doing this is concerned:
- Use the SB-250, and maybe mess up the shoulder of the wheel, that I can always true back in shape later ?
- Use the DF-250, and use as always very light pressure, at the risk of of creating a small zone with higher wear than on the rest of the wheel ?

To be clear, the intent is not sharpening hundreds of brad point bits, just getting my dear ones back in shape.

Offline RickKrung

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Re: Modification of the DBS-22 By Kurt Johansson of Sweden
« Reply #19 on: March 19, 2021, 03:19:27 pm »
I know I'm unearthing an old subject, but I have a few Festool brad point bits that have gotten quite dull.

So I think this modification might help a lot, as the Tormek is the only grinder I can use for this. I was wondering what you would suggest as far as the wheel for doing this is concerned:
- Use the SB-250, and maybe mess up the shoulder of the wheel, that I can always true back in shape later ?
- Use the DF-250, and use as always very light pressure, at the risk of of creating a small zone with higher wear than on the rest of the wheel ?

To be clear, the intent is not sharpening hundreds of brad point bits, just getting my dear ones back in shape.

This is a good question.  If your "dear ones" are just a few, I would probably use the SB stone rather than risk the DF.  And I suppose it depends on how much grinding is needed to return them to good service.  The latter is why I would consider using a traditional grinding wheel, such as the Norton 3X, for initial work, as it will take metal off faster and is cheap enough to be sacrificial without inflicting that loss on the SB.  Also, I think it would not cause much wear on a traditional wheel, so there really would not be much "sacrifice". 

I have such wheels set up on my T8, so it is easy for me to consider this. This post by Ken S is what started it for me and I have posted many times here about the benefits and use of traditional grinding wheels on Tormeks.  There has been quite a bit of discussion of locating (to buy) or making bushings to mount the usually larger arbor holes (often 1") to the 12mm Tormek shaft.  All easily doable. 

I have to caveat all this, though, that I while I have made the modification that would allow use of the DBS-22 for brad point bits, I have not actually used it for this purpose.  So I cannot say for sure that using a traditional grinding wheel would work as desired.  I just have to believe it would as it is exactly the same, except narrower. 

Final thought - try it out on one, see how much wear there is on the SB.  Judge for yourself and report back on it. 

And a PS on that final thought - these wheels are consumables (as the sage Ken S often comments).  What good is it to have them, such as an SB, if we don't use them for what we need done? 

Rick
Quality is like buying oats.  If you want nice clean, fresh oats, you must pay a fair price. However, if you can be satisfied with oats that have already been through the horse, that comes at a lower price.

Offline micha

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Re: Modification of the DBS-22 By Kurt Johansson of Sweden
« Reply #20 on: March 19, 2021, 04:08:03 pm »
This is a good question.  If your "dear ones" are just a few, I would probably use the SB stone rather than risk the DF. 

I had the same thought.  For the same reason tgbto mentioned - you can re-true the SB wheel. I wouldn't expect too much wear and tear from just grinding a few bits.

Offline tgbto

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Re: Modification of the DBS-22 By Kurt Johansson of Sweden
« Reply #21 on: March 22, 2021, 09:54:57 am »
Thank for your answers! I will modify the DBS-22 jig veeeeeeeeeery carefully and try on the SB. I will keep you posted!

Offline RickKrung

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Re: Modification of the DBS-22 By Kurt Johansson of Sweden
« Reply #22 on: March 22, 2021, 03:07:56 pm »
Thank for your answers! I will modify the DBS-22 jig veeeeeeeeeery carefully and try on the SB. I will keep you posted!

Take reasonable care, but don't stress too much on exact placement of the pivot hole.  The critical part is if you put a new clamping screw hole in, which has to rode in the curved slot, that needs to be done accurately so it slides freely. 

Rick
Quality is like buying oats.  If you want nice clean, fresh oats, you must pay a fair price. However, if you can be satisfied with oats that have already been through the horse, that comes at a lower price.

Offline tgbto

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Re: Modification of the DBS-22 By Kurt Johansson of Sweden
« Reply #23 on: April 02, 2021, 04:29:28 pm »
Here we are: I modified the jig, and the instructions are idiotproof enough that I managed to do it with a basic drill press.

So it just works, what can I say. I think it will be hard to achieve the same level of precision that we do for conical drill bits, because there are many shapes and angles of brad point bits, no template to measure them nor scale on the modified plate.

But I was able to take a cheapo drill bit to a level of sharpness it had never seen, and the resulting hole is round, precise and not noticeably wider than the bit. All that on the SB wheel, in less time than it takes to write this post.

IT takes a bit of eyeballing/fiddling with the jig to get both the face angle and the point angle right. The way I did it was : set a rough estimate of the relief angle first, then adjust the sliding knob to get a reasonable fit for the point, then adjust the relief angle more precisely, and so on. I went very slowly with the depth adjustment screw because it now not only controls the amount of metal you remove from the bit but also the height of the tip. The alignment with the marks needs to be done so that they are perpendicular to the expected faces of the point (if they're not, see picture ^^). I don't believe it is possible to have the exact same angles as the original ones, but it will be close enough that nobody will notice.

[EDIT] Using the flip-flop feature of the DBS-22 no longer guarantees symmetry, but a collar stop on the universal support could do the trick [/EDIT]

Cheers,

Nick.
« Last Edit: April 02, 2021, 05:46:20 pm by tgbto »